Update! Not that anybody reads these loooooong messages, but it keeps me organized.

Mass confusion reigns. I got the microscope. The yellow sludge on my glass which was id'd by pros as dinos doesn't seem to contain *any* life. That implies it's bacterial, too small to see with my little scope. Dinos do like to live in a bacterial sludge, but I should see some cells. I suspect user error.

Looking at filter pads, zomg! Ostreopsis ovata very clearly. BUT also some much smaller very suspicious brown, round cells. (And a virtual carnival of microcritters, including some kind of amoeba which was happily eating everything else. Very cool). Could I have several types of dinos? Is this why I'm having so much trouble getting rid of the stupid things?

Don't know if I mentioned it here, but I dosed nitrate in my tank to 3ppm with potassium nitrate. 3 days later- green algae on the glass! Very exciting as this is literally the first time I've had green algae of any sort in the tank. The algae has persisted without further additions of KNO3.